There’s no place like home. For homing pigeons, a mental map might be their ticket back.
In a new study, scientists found the migratory birds that head south in the winter have a navigational map in their minds that leads them back home. There are two theories as to how the pigeons see the world in their heads, but the findings showed how the birds determined their location and planned a flight path relative to their target.
"Pigeons use their heads to fly," Nicole Blaser, a doctoral student in biology at the University of Zurich who authored the Journal of Experimental Biology study, said in a statement.
Besides using the Earth’s magnetic field, the stars and the position of the sun to determine their flight direction, pigeons were found by Blaser to possess cognitive capabilities.
Using GPS devices mounted on the homing pigeons, Blaser and her team set up three locations for the birds to navigate from: a home loft, a food loft and an unfamiliar location. The team first fed some the pigeons in a food loft, roughly 18 miles away from the home loft. Scientists then brought the birds to a third unfamiliar location and had them fly back to the home loft.
Natural obstacles prevented the pigeons from seeing the home loft, making them rely on their innate navigational skills to lead them back home. The 131 pigeons were divided into two sets: one group was fed, while the other was hungry.
"As we expected, the satiated pigeons flew directly to the home loft," Hans-Peter Lipp, neuroanatomist at UZH and Blaser's supervisor for her doctoral thesis, said in a statement. "They already started on course for their loft and only deviated from that course for a short time to make topography-induced detours."
The hungry pigeons set off on a different path, heading to the food loft first before heading home. This decision led Blaser to the conclusion that pigeons have a mental map that allows them to find home.
“The pigeons knew their geographical position in relation to the targets and chose a flight direction according to their locally manipulated needs -- clearly the essence of a cognitive navigational map,” the study says.
This isn’t the first study set to prove the mystery surrounding the secret behind homing pigeons. In January, separate findings showed the birds used low-frequency sound waves to make the mental map of their locations in their minds, LiveScience reports.
"If that sound in the Earth is coupling through the topography, then maybe the birds are actually sort of seeing, or imaging, their topography around their loft acoustically," United States Geological Survey geologist John Hagstrum told LiveScience.